Originally Posted by Gilly

Take it to the indy, mention the things you have mentioned here, and have him inspect the car for other problems you might be looking at in the next few years (bushings and suspension/steering components, other signs of developing leaks, maybe ask him to check timing chain stretch, anthing he hopefully is familiar with on this vintage car) and then do an evaluation. If you are bored with the car and want something new, be honest with yourself, if you do still like the car, I don't see a problem in dumping money in to it if there is no signs of impending disaster. You know the history of the car and that counts for a lot.
If bailing out is in the future you could consider possibly a later 210 chassis wagon, unless as you say the rust out too badly where you live. The MLs seem to hold up body-wise, have you considered one of those?